Magnesium oxide-carboxylate complexes, method for their preparation, and compositions containing the same

ABSTRACT

Thixotropic magnesium-containing complexes are prepared by heating a mixture of magnesium hydroxide, magnesium oxide, hydrated magnesium oxide or a magnesium alkoxide; a carboxylic acid, a mixture thereof with a sulfonic or pentavalent phosphorus acid, or an ester or salt of either of these; water (optional under certain conditions); and an organic solubilizing agent (which may be liquid or solid at ambient temperature) for the acid or ester. The amount of magnesium is such as to provide a basic composition. The resulting complexes may be obtained in liquid or solid form, and are useful as additives for lubricants and fuels and as protective coating compositions for metal surfaces (such as automotive undercoats and frame coatings).

RELATED APPLICATIONS

This application is a continuation-in-part of copending application Ser.No. 882,511, filed Mar. 1, 1978, now abandoned. Said application is adivision of application Ser. No. 760,315, filed Jan. 18, 1977, now U.S.Pat. No. 4,094,801, which in turn is a continuation-in-part ofapplication Ser. No. 681,627, filed Apr. 29, 1976, now abandoned.

INTRODUCTION AND SUMMARY OF THE INVENTION

This invention relates to new magnesium-containing compositions ofmatter and methods for their preparation. In a general sense, theinvention comprises thixotropic noncarbonated magnesium-containingcomplexes which are prepared by heating, at a temperature above about30° C., a mixture comprising:

(A) At least one of magnesium hydroxide, magnesium oxide, hydratedmagnesium oxide and a magnesium alkoxide;

(B) At least one oleophilic organic reagent comprising a carboxylicacid, a mixture of a major amount thereof with a minor amount of asulfonic acid or pentavalent phosphorus acid, or an ester or alkalimetal or alkaline earth metal salt of either of these;

(C) Water, if necessary to convert a substantial proportion of componentA to magnesium hydroxide or hydrated magnesium oxide; and

(D) At least one organic solubilizing agent for component B;

the ratio of equivalents of magnesium to the acid portion of component Bbeing at least about 5:1; and the amount of water present, if any, beingsufficient to hydrate a substantial proportion of component A calculatedas magnesium oxide.

Several methods are known for the preparation of basic magnesiumcompounds for use in lubricants, greases and the like. For example, U.S.Pat. No. 3,865,737 describes the formation of a highly basicmagnesium-containing liquid dispersion by mixing an oil-solubledispersing agent, magnesium oxide, a volatile aliphatic hydrocarbonsolvent, alcohol, water and ammonia or an ammonium compound, treatingthe mixture with carbon dioxide, adding a non-volatile diluent oil andremoving volatiles. Similarly, U.S. Pat. No. 3,629,109 describes thecarbonation of a mixture of an oil-soluble organic acid or salt thereof,magnesium oxide, a lower aliphatic alcohol, water and an organic liquiddiluent. The products obtained by these methods may be characterized,for the most part, as basic oleophilic magnesium carbonates since anessential step in their preparation is reaction with carbon dioxide.

In accordance with the present invention, it has been discovered thathighly basic, thixotropic magnesium complexes may be prepared withoutreaction with carbon dioxide or similar acidic gases. The productsobtained in accordance with the present invention, which may becharacterized as complexes of magnesium oxide or hydroxide and amagnesium salt of the acid comprising component B, and which arehereinafter sometimes referred to merely as "magnesium complexes", havea wide variety of uses, including additives for lubricants and fuel oilsand corrosion-resistant coatings or constituents thereof.

A principal object of the present invention, therefore, is to providenew oleophilic magnesium-containing compositions and a method for theirpreparation.

A further object is to provide a method for producing magnesiumcomplexes which does not necessitate reaction with carbon dioxide or asimilar acidic gas.

A further object is to provide basic thixotropic magnesium compositionswhich may be obtained either in liquid or solid form.

Still another object is to provide thixotropic magnesium-containingcompositions useful as greases, as detergent additives for lubricants oras corrosion inhibitors, vanadium scavengers and smoke suppressants forfuels, and in the formulation of corrosion-resistant coatings formetals.

Other objects will in part be obvious and will in part appearhereinafter.

COMPONENT A

Component A used in the method of this invention is magnesium hydroxide,magnesium oxide, hydrated magnesium oxide, a magnesium alkoxide, or amixture of these. Magnesium hydroxide and magnesium oxide are, ofcourse, represented by the formulas Mg(OH)₂ and MgO, respectively.Magnesium oxide exists in an inactive "dead burned" and a hydratable"reactive" form and the latter is the one which is useful in thisinvention although mixtures of the "reactive" form with minor amounts ofthe "dead burned" form may also be used. "Hydrated magnesium oxide", forthe purpose of this invention, is magnesium oxide which is associatedwith water in an amount less than that required for conversion tomagnesium hydroxide; that is, the amount of water is less than one moleper mole of magnesium oxide. As so defined, "hydrated magnesium oxide"may actually be a mixture of various proportions of magnesium oxide andmagnesium hydroxide and its exact chemical nature is not critical tothis invention. Typically, the amount of water present in "hydratedmagnesium oxide" is at least about 0.7 mole per mole of the oxide.

The magnesium alkoxides, especially the lower alkoxides (i.e., those inwhich the alkyl groups contain 7 carbon atoms or less), are equivalentto magnesium oxide and hydroxide for the purpose of this invention; theyare hydrolyzed by water to magnesium hydroxide under the conditionsdescribed hereinafter.

The equivalent weight of component A is half its molecular weight, sincemagnesium is a divalent element.

COMPONENT B

Component B is at least one oleophilic reagent comprising a carboxylicacid or a mixture thereof with a sulfonic acid, or salts or estersthereof. These acids include many of those known to be susceptible tooverbasing and especially many of those disclosed in a number of U.S.patents such as Nos. 2,616,904; 2,695,910; 3,312,618; 3,746,643;3,764,533; and the aforementioned 3,629,109. Those patents areincorporated by reference herein for their disclosure of suitable acidicoleophilic reagents.

The carboxylic acids suitable for use as component B include aliphatic,cycloaliphatic and aromatic mono- and polybasic carboxylic acids freefrom acetylenic unsaturation, including naphthenic acids, alkyl- oralkenyl-substituted cyclopentanoic acids, alkyl- or alkenyl-substitutedcyclohexanoic acids, and alkyl- or alkenyl-substituted aromaticcarboxylic acids. The aliphatic acids generally contain from about 8 toabout 50, and preferably from about 12 to about 25, carbon atoms. Thecycloaliphatic and aliphatic carboxylic acids are preferred and they canbe saturated or unsaturated. Specific examples include 2-ethylhexanoicacid, linolenic acid, propylene tetramersubstituted maleic acid, behenicacid, isostearic acid, pelargonic acid, capric acid, palmitoleic acid,linoleic acid, lauric acid, oleic acid, ricinoleic acid, undecylic acid,dioctylcyclopentanecarboxylic acid, myristic acid,dilauryldecahydronaphthalenecarboxylic acid,stearyl-octahydroindenecarboxylic acid, palmitic acid, alkyl- andalkenylsuccinic acids, acids formed by oxidation of petrolatum or ofhydrocarbon waxes, and commercially available mixtures of two or morecarboxylic acids such as tall oil acids, rosin acids, and the like.

The above-described carboxylic acids may be used in admixture with aminor amount of a sulfonic or pentavalent phosphorus acid; that is,component B may comprise a mixture containing more than 50% by weight ofcarboxylic acids and less than 50% of sulfonic or pentavalent phosphorusacids. Suitable sulfonic acids include those represented by the formulasR¹ (SO₃ H)_(r) and (R²)_(x) T(SO₃ H)_(y). In these formulas, R¹ is analiphatic or aliphatic-substituted cycloaliphatic hydrocarbon oressentially hydrocarbon radical free from acetylenic unsaturation andcontaining up to about 60 carbon atoms. When R¹ is aliphatic, it usuallycontains at least about 15 carbon atoms; when it is analiphatic-substituted cycloaliphatic radical, the aliphatic substituentsusually contain a total of at least about 12 carbon atoms. Examples ofR¹ are alkyl, alkenyl and alkoxyalkyl radicals, andaliphatic-substituted cycloaliphatic radicals wherein the aliphaticsubstituents are alkyl, alkenyl, alkoxy, alkoxyalkyl, carboxyalkyl andthe like. Generally, the cycloaliphatic nucleus is derived from acycloalkane or a cycloalkene such as cyclopentane, cyclohexane,cyclohexene or cyclopentene. Specific examples of R.sup. 1 arecetylcyclohexyl, laurylcyclohexyl, cetyloxyethyl, octadecenyl, andradicals derived from petroleum, saturated and unsaturated paraffin wax,and olefin polymers including polymerized monoolefins and diolefinscontaining about 2-8 carbon atoms per olefinic monomer unit. R¹ can alsocontain other substituents such as phenyl, cycloalkyl, hydroxy,mercapto, halo, nitro, amino, nitroso, lower alkoxy, loweralkylmercapto, carboxy, carbalkoxy, oxo or thio, or interrupting groupssuch as --NH--, --O-- or --S--, as long as the essentially hydrocarboncharacter thereof is not destroyed.

R² is generally a hydrocarbon or essentially hydrocarbon radical freefrom acetylenic unsaturation and containing from about 4 to about 60aliphatic carbon atoms, preferably an aliphatic hydrocarbon radical suchas alkyl or alkenyl. It may also, however, contain substituents orinterrupting groups such as those enumerated above provided theessentially hydrocarbon character thereof is retained. In general, thenon-carbon atoms present in R¹ or R² do not account for more than 10% ofthe total weight thereof.

The radical T is a cyclic nucleus which may be derived from an aromatichydrocarbon such as benzene, naphthalene, anthracene or biphenyl, orfrom a heterocyclic compound such as pyridine, indole or isoindole.Ordinarily, T is an aromatic hydrocarbon nucleus, especially a benzeneor naphthalene nucleus.

The subscript x is at least 1 and is generally 1-3. The subscripts r andy have an average value of about 1-4 per molecule and are generally also1.

Illustrative sulfonic acids useful as part of component B are mahoganysulfonic acids, petrolatum sulfonic acids, mono- and polywax-substitutednaphthalene sulfonic acids, cetylchlorobenzene sulfonic acids,cetylphenol sulfonic acids, cetylphenol disulfide sulfonic acids,cetoxycapryl benzene sulfonic acids, dicetyl thianthrene sulfonic acids,dilauryl β-naphthol sulfonic acids, dicapryl nitronaphthalene sulfonicacids, paraffin wax sulfonic acids, unsaturated paraffin wax sulfonicacids, hydroxy-substituted paraffin wax sulfonic acids, tetraisobutylenesulfonic acids, tetra-amylene sulfonic acids, chloro-substitutedparaffin wax sulfonic acids, nitroso-substituted paraffin wax sulfonicacids, petroleum naphthene sulfonic acids, cetylcyclopentyl sulfonicacids, lauryl cyclohexyl sulfonic acids, mono- and polywax-substitutedcyclohexyl sulfonic acids, postdodecylbenzene sulfonic acids, "dimeralkylate" sulfonic acids, and the like. These sulfonic acids arewell-known in the art and require no further discussion herein.

The pentavalent phosphorus acids useful as part of component B may berepresented by the formula ##STR1## wherein each of R³ and R⁴ ishydrogen or a hydrocarbon or essentially hydrocarbon radical preferablyhaving from about 4 to about 25 carbon atoms, at least one of R³ and R⁴being hydrocarbon or essentially hydrocarbon; each of X¹, X², X³ and X⁴is oxygen or sulfur; and each of a and b is 0 or 1. Thus, it will beappreciated that the phosphorus acid may be an organophosphoric,phosphonic or phosphinic acid, or a thio analog of any of these.

Usually, the phosphorus acids are those of the formula ##STR2## whereinR³ is a phenyl radical or (preferably) an alkyl radical having up to 18carbon atoms, and R⁴ is hydrogen or a similar phenyl or alkyl radical.Mixtures of such phosphorus acids are often preferred because of theirease of preparation.

Also useful as component B are the alkali metal and alkaline earth metalsalts (e.g., sodium, potassium, magnesium, calcium, strontium or bariumsalts, with magnesium salts being preferred) and esters of the acidspreviously described. The suitable esters include those with monohydricalcohols free from acetylenic unsaturation and having from about 1 toabout 25 carbon atoms, including monohydric alcohols such as methanol,ethanol, the butanols, the hexanols, allyl alcohol, crotyl alcohol,stearyl alcohol and oleyl alcohol, and polyhydric alcohols such asethylene glycol, diethylene glycol, propylene glycol, glycerol,sorbitol, sorbitan and similar carbohydrates and derivatives ofcarbohydrates.

It will be appreciated from the above description of component B that itcomprises an organic acid or a compound hydrolyzable thereto. The ratioof equivalents of magnesium to equivalents of acid is important in thecontext of the invention, and so the equivalent weight of the acidportion of component B must be defined.

Obviously, to the extent that component B is a free acid its equivalentweight is its molecular weight divided by the number of acidic groupspresent per molecule. To the extent component B is an ester or salt of acarboxylic or sulfonic acid, it is considered to be convertible to thefree acid during the reaction with component A and water and itsequivalent weight is similarly calculated. To the extent that componentB is a phosphorus acid or a salt or ester thereof, its equivalent weightis its molecular weight divided by the sum of the acidic hydroxy groupsbonded to phosphorus (or salts thereof) and the number of ester groupshydrolyzable to such hydroxy groups (or salts thereof) under thereaction conditions of the invention. If any ester groups remainunhydrolyzed, the ester is considered inert to that extent for thepurpose of calculating equivalent weight.

The preferred compounds for use as component B are the above-describedcarboxylic acids having an equivalent weight between about 200 and about500 and mixtures thereof with sulfonic acids of similar molecularweight, especially alkylaromatic sulfonic acids and more particularlyalkylbenzenesulfonic acids.

One of the characteristics of component B is that it is oleophilic. Thismeans that it is soluble or at least stably dispersible (as definedhereinafter) in oil or similar non-polar organic liquids such as hexane,naphtha, Stoddard solvent, benzene, toluene and the like. Whilecomponent B need not be oil-soluble, the oil-soluble acids are preferredfor the purposes of this invention. These oil-soluble compoundsconstitute a known subgenus of the previously described compounds usefulas component B.

COMPONENT C

Component C is water, which may be used in the liquid or vapor phase andis under certain conditions optional (as described hereinafter). For thepurpose of the present invention, the equivalent weight of water isconsidered to be 9 (half its molecular weight).

COMPONENT D

Component D is at least one organic solubilizing agent for component B.It may be solid or liquid at room temperature, although liquids areoften preferred. It need not be a solvent for component B, in the sensethat component B is entirely soluble therein when in the liquid state,but should be at least a partial solvent in the sense that relativelysmall proportions of component B, at least, when blended with componentD in the liquid state will form a homogeneous mixture.

Materials useful as component D include substantially inert, normallyliquid organic diluents. The term "substantially inert" as used hereinis intended to mean that the diluent is inert to chemical or physicalchange under the conditions in which it is used so as not to materiallyinterfere in an adverse manner with the preparation, storage, blendingand/or functioning of the magnesium complex in the content of itsintended use. For example, small amounts of a diluent can undergominimal reaction or degradation without preventing the making and usingof the invention as described herein. In other words, such reaction ordegradation, while technically discernible, would not be sufficient todeter the practical worker of ordinary skill in the art from making andusing the invention for its intended purposes. "Substantially inert" asused herein is thus readily understood and appreciated by those ofordinary skill in the art.

Among the preferred normally liquid diluents are non-polar compounds ormixtures of compounds such as naphtha, hexane, kerosene, mineral oil,Stoddard solvent, benzene, toluene, xylene, low molecular weightpolybutenes, and alkylbenzenes of the type present as unsulfonatedresidue in alkylbenzenesulfonic acids. Also suitable are somewhat morepolar liquids such as 1-butanol, 2-butanol, ethylene glycol, propyleneglycol, ethylene glycol monomethyl ether, ethylene glycol monobutylether, ethylene glycol dimethyl ether, diethylene glycol and its ethers,wax-derived alcohol mixtures, methyl ethyl ketone, chlorobenzene,pyridine, indole, furan and tetrahydrofuran.

Also useful are substantially inert materials which are solid at ambienttemperature, and which may be chemically similar to the above-describedliquids. These include the following:

1. Waxes, such as:

Crystalline (including microcrystalline) wax

Paraffin wax

Petrolatum wax

Beeswax

Bohemia wax

Hydrogenated castor oil

Lanolin

Shellac wax

Spermaceti

Carnauba wax

Candelilla wax

Chlorinated naphthalene

Waxy alcohol mixtures (e.g., C₂₀₋₄₀ aliphatic alcohols)

Other wax materials of the type disclosed in Kirk-Othmer, Encyclopediaof Chemical Technology, Second Edition, vol. 22, pp. 156-173 (which isincorporated by reference herein for such disclosure)

2. Hydrocarbon and similar resins, such as:

Olefin polymer resins and waxes (e.g., polyethylene, polypropylene)

Terpene resins

Coumarone-indene resins

Phenolic and alkylated phenolic resins

Furan resins

3. Natural resins, such as:

Copal

Manila chips

Gum damar

Accroides gum

Rosin

Hydroabietyl alcohol resin

4. Addition polymer resins, such as:

Styrene-butadiene

Hydrogenated styrene-butadiene

Polystyrene and poly(α-methylstyrene)

Olefin-vinyl acetate copolymers

Polyvinyl acetate

Polyvinyl chloride

Vinyl acetate-vinyl chloride copolymers

Acrylic resins

Solid polybutenes

5. Polyester resins

6. Solid plasticizers, such as:

Triethylene glycol dibenzoate

Neopentyl glycol dibenzoate

Glyceryl tribenzoate

It is also within the scope of the invention to use mixtures of any ofthe materials described above. Such mixtures may be of materials all ofwhich are liquid at normal ambient temperatures (e.g., about 20°-30°C.), such as mineral oil-toluene, Stoddard solvent-toluene, mineraloil-alkylbenzene, Stoddard solvent-alkylbenzene; of materials all ofwhich are solid at normal ambient temperatures, such as paraffinwax-polyethylene wax, paraffin wax-polyethylene wax-C₂₀₋₄₀ alcohol wax;or of materials which are both liquid and solid at normal ambienttemperatures, such as mixtures of the above-mentioned normally liquiddiluents and a resin of hydrocarbon wax (e.g., paraffin wax-toluene,polypropylene-toluene, polypropylene-mineral oil).

COMPONENT PROPORTIONS

The relative proportions of components A, B, C and D are an importantfeature of this invention since the physical state in which themagnesium complex is obtained depends to a great extent on theproportions of the components used for their preparation.

As previously noted, the ratio of equivalents of magnesium to the acidportion of component B is at least about 5:1. This ratio is hereinaftersometimes referred to as the "magnesium ratio". (It will be appreciatedthat the magnesium ratio is such as to produce a basic magnesiumcomplex.) If component B is a free carboxylic acid or an ester or saltthereof with a metal other than magnesium, the ratio of component A tocomponent B will be identical to the magnesium ratio. If component B isa magnesium salt, the ratio of component A to component B will besomewhat less than the magnesium ratio since part of the magnesium isprovided by component B.

It has been found that magnesium complexes with relatively low magnesiumratios (e.g., from about 5:1 to about 21:1 and particularly from about5:1 to about 10:1) are particularly useful as lubricant additives.Complexes with a magnesium ratio above about 60:1 and preferably up toabout 150:1 find utility principally as additives for fuel oils. Asprotective coatings for metals, it is preferred to employ complexes inwhich component D is entirely or predominantly liquid and the magnesiumratio is between about 25:1 and about 60:1, or solid (e.g., "hot melt")complexes in which component D is entirely or predominantly solid atambient temperature and which typically have a magnesium ratio fromabout 5:1 to about 50:1.

The ratio of moles of water (component C) to gram-atoms of magnesium incomponent A (said ratio hereinafter sometimes designated the "waterratio") is also critical. When component A is substantially allmagnesium hydroxide or hydrated magnesium oxide, the presence of wateris frequently not required. If water is not present, however, complexpreparation usually requires extremely efficient high-speed mixing(e.g., by mixers such as that sold under the trade name "Dispersator" byPremier Mill Corporation) so as to produce a uniform product. When asubstantial portion of component A is magnesium oxide or a magnesiumalkoxide, the presence of water as component C is required.

Most often, the use of water is advantageous regardless of the identityof component A. When it is present, the amount of water should be atleast sufficient to hydrate a substantial proportion of component A,calculated as magnesium oxide. The proportion of additional water overand above that amount will depend on the nature of the product desiredand the intended use thereof. If component A is anhydrous magnesiumoxide the water ratio should generally be at least about 0.7:1 so as toproduce a substantial proportion of the hydrated magnesium oxidereferred to hereinabove.

A water ratio up to about 3.0:1, and especially from about 0.7:1 toabout 3.0:1, is usually adequate to produce a composition of thisinvention. If larger amounts of water than this are used, it isfrequently possible to remove excess water, at least some of whichseparates from the magnesium complex as a separate layer and theremainder of which can be removed by azeotropic distillation or thelike. More water may be desirable for the preparation of the complex incertain instances; for example, magnesium oxide frequently containstraces of sodium compounds whose presence may be undesirable in thecomplex, and if so, such compounds may be removed by using up to about 8moles of water per mole of component A and removing the excess, whichhas dissolved therein the sodium compounds. When the excess water hasbeen removed, the molar ratio of remaining water to component A isusually below about 3:1 as noted above.

As among various magnesium complexes with water ratios between about0.7:1 and about 3.0:1, those having a water ratio below about 1:1 areoften particularly useful as lubricant additives or fuel oil additives,while those having a somewhat higher water ratio (e.g., between about1:1 and 3:1) may be particularly useful in the preparation ofcorrosion-resistant coating compositions.

The ratio of component D to component A is not critical and may bevaried so as to provide magnesium complexes suitable for the particularuse for which they are intended. For example, a complex suitable as alubricant additive may frequently be obtained by employing as componentD solely the unsulfonated alkylbenzene present as an impurity in thesulfonic acid used as component B. In that event, the weight ratio ofcomponent D to component A will usually be below about 1:1 andfrequently as low as 0.5-0.7:1. In general, when a lubricant additiveproduct is desired it is inadvisable to use volatile materials ascomponent D.

When the magnesium complex is to be used as a fuel oil additive, higheramounts of component D are frequently preferred and these may includerelatively volatile materials such as toluene or xylene, less volatilematerials such as mineral oil or mineral seal oil, and mixtures ofvolatile and less volatile materials. The proportions of volatile andnon-volatile solubilizing agents in such mixtures are subject to widevariation, but in any event it is usually found that the total weightratio of component D to component A should be from about 1.2:1 to about1.8:1.

When a product useful in a protective metal coating is desired, stillhigher ratios (e.g., from about 2:1 to about 3:1) are often employedwith one of the solubilizing agents being a substantially volatilealiphatic hydrocarbon such as naphtha or Stoddard solvent, and the otherbeing a somewhat less volatile material such as mineral oil. Anotheruseful type of complex for metal coating is the solid (e.g., "hot melt")type briefly referred to hereinabove, in which component D comprisesmostly or entirely materials which are solid at ambient temperature, inwhich case the ratio of D to A may be between about 0.5:1 and about 6:1.

PREPARATION OF THE MAGNESIUM COMPLEX

The magnesium complexes of this invention are prepared by merelyblending the components described hereinabove and heating the resultingblend at a temperature above about 30° C. It is important that water (ifpresent as component C) remain in the blend during substantially theentire period of preparation of the magnesium complex, and the maximumtemperature thereof should be adjusted accordingly. However, said watermay be present in the liquid or vapor state, i.e., as liquid water or assteam, though it will be apparent to those skilled in the art that thepreparation of complexes involving a relatively large amount of waterwill be difficult if not impossible, at least at atmospheric pressure,if the water is present as steam. Therefore, it is generally found thattemperatures between about 30° and about 125° C. are most convenientlyemployed at atmospheric pressure, and the preparation should be carriedout under superatmospheric pressure if the use of higher temperatures islikely. Most often, a maximum temperature of about 100° C. is convenientwhen component D is entirely or predominantly liquid and the preferredtemperature range is then between about 40° and about 90° C. Naturally,the temperature may be somewhat higher (e.g., between about 95° andabout 150° C.) when component D is entirely or predominantly a solid atambient temperature.

The order of addition of the various components is not critical. It isoften convenient to first combine components A, B and D and subsequentlyto add component C (water) either all at once or incrementally. It isalso often found convenient to prepare an initial mixture containingonly a relatively small portion of component A (e.g., from about 5% toabout 10% of the total amount thereof) and to add the remainder at alater stage, typically during or after the addition of water. Finally,it is within the scope of the invention to prepare the magnesium complexusing only a portion of the amount of component D intended, and to addthe remainder after the complex has been prepared. The amountsubsequently added is generally less than about 50% and preferably lessthan about 40% by weight of the total amount to be used. This subsequentaddition of part of component D is most often useful when component D ispartly or entirely solid (for example, when it comprises waxes and/orresins) and/or when it imparts additional desirable properties such asmodifying fluidity under the conditions of use.

The magnesium complexes of this invention are thixotropic; that is, theydecrease in viscosity when agitated and return to approximately theiroriginal viscosity after agitation ceases. When component D ispredominantly liquid, the complexes are typically viscous liquids orheterogeneous dispersions in the form of greases or gels. When componentD is predominantly solid, the magnesium complex may be a solid "hotmelt" type material.

The solid materials are useful for many purposes, such as for theformation of corrosion-resistant coatings as described hereinafter. Forsome other applications, such as those involving lubricants and fuels,the complex is preferably obtained in the form of a relativelynon-viscous, easily flowable liquid. Such liquids may be obtained bymethods well known to those of skill in the art, such as by maximizingthe amount of liquid diluent present as component D or by decreasing therelative amount of component A or component C in the reaction mixture.Alternatively, a viscous or solid complex can be further diluted with asubstantially inert organic liquid diluent of the type describedhereinabove to produce a homogeneous solution. One of the unique anddesirable characteristics of the thixotropic compositions of thisinvention is their capability of existing either as heterogeneouscompositions or homogeneous, relatively dilute solutions or dispersions.

A method which is sometimes advantageous for incorporating relativelylarge amounts of magnesium while making possible the formation of ahomogeneous solution or dispersion in mineral oil or the like is toprepare the complex in the presence of ammonium hydroxide, which may beprepared from ammonia and the water present as component C. The amountof ammonium hydroxide required is small, generally less than about 10%by weight based on the water present. Insoluble materials can then beremoved by diluting with a non-polar volatile organic liquid such ashexane or naphtha, centrifuging, and stripping the volatile liquid, orby equivalent means.

Another method for clarifying the magnesium complex for use in mineraloil, which may be employed in addition to or in place of preparation inthe presence of ammonium hydroxide, is to add water or an acidic orbasic reagent after preparation of the complex. The acidic or basicreagent may be organic or inorganic; suitable ones include sodiumhydroxide, potassium hydroxice, ammonium hydroxide, triethanolamine,tartaric acid and citric acid. The amount of water or acidic or basicreagent is generally less than about 10% by weight of the magnesiumcomplex system.

The stability of the magnesium complexes of this invention is oftenimproved if a minor effective amount of an oxidation inhibitor isincorporated therein. Suitable oxidation inhibitors include the hinderedphenol type, illustrated by 2,6-di-t-butylphenol and its derivatives;and the arylamine type, illustrated by phenyl-α-naphthylamine. Theamount of antioxidant required is usually between about 0.1% and about2% and preferably between about 0.2% and 1% by weight. Oxidationinhibitors are particularly useful in the corrosion-resistant coatingcompositions of this invention since they inhibit viscosity decreasesthereof.

The preparation of the magnesium complexes of this invention isillustrated by the following examples. All parts are by weight.

EXAMPLE 1

A mixture of 754 parts of water, 23 parts of magnesium oxide, 210 partsof mineral oil and 247 parts of Stoddard solvent is heated to about 40°C. and 331 parts of a carboxylic acid having an equivalent weight ofabout 350 and obtained by oxidation of petrolatum, which acid has beenpreheated to about 50°-60° C., is added as the temperature of themixture is maintained at 40°-45° C. An additional 350 parts of magnesiumoxide is added, with stirring, and the temperature of the mixture isincreased to 75° C. An opaque dispersion is obtained which is screenedto afford the desired magnesium oxide-carboxylate complex.

EXAMPLE 2

A product similar to that of Example 1 is prepared, substituting about300 parts of sorbitan trioleate for the oxidized petrolatum.

EXAMPLE 3

A mixture of 16 parts of an alkylbenzenesulfonic acid having anequivalent weight of about 430 and containing about 22% unsulfonatedalkylbenzene, 305 parts of mineral oil, 180 parts of magnesium oxide and96 parts of "Hydrex 440", a mixture of hydrogenated fatty acidsobtainable from Union Camp Corporation, is heated to 95° C. and blownwith steam for two hours. The temperature is increased to 145°-150° C.,an additional 28 parts of mineral oil is added and the mixture is blownwith air as the temperature is heated to 170° C. over 15 minutes. Themixture is then cooled to room temperature and an additional 44 parts ofmineral oil is added to yield the desired magnesiumoxide-carboxylatesulfonate complex having the consistency of a grease.

LUBRICANTS AND FUELS

When in the form of flowable liquids as previously described, themagnesium complexes of this invention are stably dispersible in thenormally liquid media (e.g., oil, fuel, etc.) in which they are intendedto function. Thus, for example, compositions intended for use in oilsare stably dispersible in an oil in which they are to be used. The term"stably dispersible" as used in the specification and appended claims isintended to mean the magnesium complex or other material is capable ofbeing dispersed in a given medium to an extent which allows it tofunction in its intended manner. Thus, for example, when a magnesiumcomplex is used in an oil, it is sufficient that it be capable of beingsuspended in the oil in an amount sufficient to enable the oil topossess one or more of the desired properties imparted to it by thesuspended complex. Such suspension can be achieved in variousconventional ways. For example, in constantly circulating oil or oil insplash lubricating systems, physical agitation can keep the complexsuspended in oil. Likewise, conventional dispersants (such as theacylated nitrogen dispersants disclosed in U.S. Pat. No. 3,219,666)often found in lubricating oils and fuels promote the stable dispersionor suspension of the magnesium complex. In any event, the complex willbe "stably dispersible" in the normally liquid media in which it will beused in at least the minimum concentrations set forth elsewhere herein.Thus, the terminology "stably dispersible" is used in a conventionalmanner and will be understood by those of ordinary skill in the art.

As previously indicated, the magnesium complexes of this invention maybe homogeneously incorporated into lubricants, in which they functionprimarily as ash-producing detergents. They can be employed in a varietyof lubricants based on diverse oils of lubricating viscosity, includingnatural and synthetic lubricating oils and mixtures thereof. Theselubricants include crankcase lubricating oils for spark-ignited andcompression-ignited internal combustion engines, including automobileand truck engines, two-cycle engines, aviation piston engines, marineand railroad diesel engines, and the like. They can also be used in gasengines, stationary power engines and turbines and the like. Automatictransmission fluids, transaxle lubricants, gear lubricants,metal-working lubricants, hydraulic fluids and other lubricating oil andgrease compositions can also benefit from the incorporation therein ofthe compositions of the present invention.

Natural oils include animal oils and vegetable oils (e.g., castor oil,lard oil) as well as liquid petroleum oils and solvent-treated oracid-treated mineral lubricating oils of the paraffinic, naphthenic ormixed paraffinic-naphthenic types. Oils of lubricating viscosity derivedfrom coal or shale are also useful base oils. Synthetic lubricating oilsinclude hydrocarbon oils and halo-substituted hydrocarbon oils such aspolymerized and interpolymerized olefins [e.g., polybutylenes,polypropylenes, propylene-isobutylene copolymers, chlorinatedpolybutylenes, poly(1-hexenes), poly(1-octenes), poly(1-decenes), etc.and mixtures thereof]; alkylbenzenes (e.g., dodecylbenzenes,tetradecylbenzenes, dinonylbenzenes, di(2-ethylhexyl)benzenes, etc.);polyphenyls (e.g., biphenyls, terphenyls, alkylated polyphenyls, etc.),alkylated diphenyl ethers and alkylated diphenyl sulfides and thederivatives, analogs and homologs thereof and the like.

Alkylene oxide polymers and interpolymers and derivatives thereof wherethe terminal hydroxyl groups have been modified by esterification,etherification, etc. constitute another class of known syntheticlubricating oils. These are exemplified by the oils prepared throughpolymerization of ethylene oxide or propylene oxide, the alkyl and arylethers of these polyoxyalkylene polymers (e.g., methyl-polyisopropyleneglycol ether having an average molecular weight of 1000, diphenyl etherof polyethylene glycol having a molecular weight of 500-1000, diethylether of polypropylene glycol having a molecular weight of 1000-1500,etc.) or mono- and polycarboxylic esters thereof, for example, theacetic acid esters, mixed C₃ -C₈ fatty acid esters, or the C₁₃ Oxo aciddiester of tetraethylene glycol.

Another suitable class of synthetic lubricating oils comprises theesters of dicarboxylic acids (e.g., phthalic acid, succinic acid, alkylsuccinic acids and alkenyl succinic acids, maleic acid, azelaic acid,suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic aciddimer, malonic acid, alkyl malonic acids, alkenyl malonic acids, etc.)with a variety of alcohols (e.g., butyl alcohol, hexyl alcohol, dodecylalcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycolmonoether, propylene glycol, etc.). Specific examples of these estersinclude dibutyl adipate, di(2-ethylhexyl) sebacate, di-n-hexyl fumarate,dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctylphthalate, didecyl phthalate, dieicosyl sebacate, the 2-ethylhexyldiester of linoleic acid dimer, the complex ester formed by reacting onemole of sebacic acid with two moles of tetraethylene glycol and twomoles of 2-ethylhexanoic acid, and the like.

Esters useful as synthetic oils also include those made from C₅ to C₁₂monocarboxylic acids and polyols and polyol ethers such neopentylglycol, trimethylolpropane, pentaerythritol, dipentaerythritol,tripentaerythritol, etc.

Silicon-based oils such as the polyalkyl-, polyaryl-, polyalkoxy-, orpolyaryloxy-siloxane oils and silicate oils comprise another usefulclass of synthetic lubricants (e.g., tetraethyl silicate, tetraisopropylsilicate, tetra-(2-ethylhexyl) silicate, tetra-(4-methyl-2-ethylhexyl)silicate, tetra-(p-tert-butylphenyl) silicate,hexa-(4-methyl-2-pentoxy)-disiloxane, poly(methyl)-siloxanes,poly(methylphenyl)siloxanes, etc.). Other synthetic lubricating oilsinclude liquid esters of phosphorus-containing acids (e.g., tricresylphosphate, trioctyl phosphate, diethyl ester of decylphosphonic acid,etc.), polymeric tetrahydrofurans and the like.

Unrefined, refined and rerefined oils (and mixtures of each with eachother) of the type disclosed hereinabove can be used in the lubricantcompositions of the present invention. Unrefined oils are those obtaineddirectly from a natural or synthetic source without further purificationtreatment. For example, a shale oil obtained directly from retortingoperations, a petroleum oil obtained directly from an esterificationprocess and used without further treatment would be an unrefined oil.Refined oils are similar to the unrefined oils except they have beenfurther treated in one or more purification steps to improve one or moreproperties. Many such purification techniques are known to those ofskill in the art such as solvent extraction, acid or base extraction,filtration, percolation, etc. Rerefined oils are obtained by processessimilar to those used to obtain refined oils applied to refined oilswhich have been already used in service. Such rerefined oils are alsoknown as reclaimed or reprocessed oils and often are additionallyprocesses by techniques directed to removal of spent additives and oilbreakdown products.

Generally, the lubricants of the present invention contain an amount ofthe magnesium complex of this invention sufficient to impart detergencythereto. Normally this amount will be from about 0.05% to about 20%,preferably from about 0.5% to about 10%, of the total weight of thelubricant. In lubricating oils operated under extremely adverseconditions, such as lubricating oils for marine diesel engines, themagnesium complexes of this invention may be present in amounts up toabout 30%.

The magnesium complexes of the present invention are also useful ascorrosion inhibitors, vanadium scavengers and smoke suppressants infuels. For that purpose, they are homogeneously incorporated in minorproportions in normally liquid fuels, usually hydrocarbonaceous fuelssuch as fuel oils, bunker fuels and the like. Normally liquid fuelcompositions comprising non-hydrocarbonaceous materials such asalcohols, ethers, organo-nitro compounds and the like (e.g., methanol,ethanol, diethyl ether, methyl ethyl ether, nitromethane) are alsowithin the scope of the invention as are liquid fuels derived fromvegetable or mineral sources such as corn, alfalfa, shale and coal.Normally liquid fuels which are mixtures of one or morehydrocarbonaceous fuels and one or more non-hydrocarbonaceous materialsare also contemplated.

Generally, these fuel compositions contain an amount of the magnesiumcomplex sufficient to impart corrosion resistance thereto, suppresssmoke or serve as a vanadium scavenger; usually this amount is fromabout 1 to about 10,000, preferably from about 4 to about 1000, partsthereof by weight per million parts of fuel.

The invention also contemplates the use of other additives incombination with the magnesium complexes. Other additives useful inlubricants include, for example, auxiliary detergents and dispersants ofthe ash-producing or ashless type, corrosion- and oxidation-inhibitingagents, pour point depressing agents, extreme pressure agents, colorstabilizers and anti-foam agents.

The auxiliary ash-producing detergents are exemplified by oil-solubleneutral and basic salts of alkali or alkaline earth metals with sulfonicacids, carboxylic acids, or organic phosphorus acids characterized by atleast one direct carbon-to-phosphorus linkage such as those prepared bythe treatment of an olefin polymer (e.g., polyisobutene having amolecular weight of 1000) with a phosphorizing agent such as phosphorustrichloride, phosphorus heptasulfide, phosphorus pentasulfide,phosphorus trichloride and sulfur, white phosphorus and a sulfur halide,or phosphorothioic chloride. The most commonly used salts of such acidsare those of sodium, potassium, lithium, calcium, magnesium, strontiumand barium.

The term "basic salt" is used to designate metal salts wherein the metalis present in stoichiometrically larger amounts than the organic acidradical. The commonly employed methods for preparing the basic saltsinvolve heating a mineral oil solution of an acid with a stoichiometricexcess of a metal neutralizing agent such as the metal oxide, hydroxide,carbonate, bicarbonate, or sulfide at a temperature above 50° C. andfiltering the resulting mass. The use of a "promoter" in theneutralization step to aid the incorporation of a large excess of metallikewise is known. Exampls of compounds useful as the promoter includephenolic substances such as phenol, naphthol, alkylphenol, thiophenol,sulfurized alkylphenol, and condensation products of formaldehyde with aphenolic substance; alcohols such as methanol, 2-propanol, octylalcohol, cellosolve, carbitol, ethylene glycol, stearyl alcohol, andcyclohexyl alcohol; and amines such as aniline, phenylenediamine,phenothiazine, phenyl-β-naphthylamine, and dodecylamine. A particularlyeffective method for preparing the basic salts comprises mixing an acidwith an excess of a basic alkaline earth metal neutralizing agent and atleast one alcohol promoter, and carbonating the mixture at an elevatedtemperature such as 60° -200° C.

Ashless detergents and dispersants are so called despite the fact that,depending on its constitution, the dispersant may upon combustion yielda non-volatile material such as boric oxide or phosphorus pentoxide;however, it does not ordinarily contain metal and therefore does notyield a metal-containing ash on combustion. Many types are known in theart, and any of them are suitable for use in the lubricants of thisinvention. The following are illustrative:

(1) Reaction products of carboxylic acids (or derivatives thereof)containing at least about 34 and preferably at least about 54 carbonatoms with nitrogen-containing compounds such as amine, organic hydroxycompounds such as phenols and alcohols, and/or basic inorganicmaterials. Examples of these "carboxylic dispersants" are described inBritish Pat. No. 1,306,529 and in many U.S. patents including thefollowing:

    ______________________________________                                        3,163,603   3,351,552      3,541,012                                          3,184,474   3,381,022      3,542,678                                          3,215,707   3,399,141      3,542,680                                          3,219,666   3,415,750      3,567,637                                          3,271,310   3,433,744      3,574,101                                          3,272,746   3,444,170      3,576,743                                          3,281,357   3,448,048      3,630,904                                          3,306,908   3,448,049      3,632,510                                          3,311,558   3,451,933      3,632,511                                          3,316,177   3,454,607      3,697,428                                          3,340,281   3,467,668      3,725,441                                          3,341,542   3,501,405      Re 26,433                                          3,346,493   3,522,179                                                         ______________________________________                                    

(2) Reaction products of relatively high molecular weight aliphatic oralicyclic halides with amines, preferably polyalkylene polyamines. Thesemay be characterized as "amine dispersants" and examples thereof aredescribed for example, in the following U.S. patents:

    ______________________________________                                        3,275,554        3,454,555                                                    3,438,757        3,565,804                                                    ______________________________________                                    

(3) Reaction products of alkyl phenols in which the alkyl group containsat least about 30 carbon atoms with aldehydes (especially formaldehyde)and amines (especially polyalkylene polyamines), which may becharacterized as "Mannich dispersants". The materials described in thefollowing U.S. patents are illustrative:

    ______________________________________                                        3,413,347        3,725,480                                                    3,697,574        3,726,882                                                    3,725,277                                                                     ______________________________________                                    

(4) Products obtained by post-treating the carboxylic, amine or Mannichdispersants with such reagents as ura, thiourea, carbon disulfide,aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinicanhydrides, nitriles, epoxides, boron compounds, phosphorus compounds orthe like. Exemplary materials of this kind are described in thefollowing U.S. patents:

    ______________________________________                                        3,036,003                                                                              3,282,955   3,493,520   3,639,242                                    3,087,936                                                                              3,312,619   3,502,677   3,649,229                                    3,200,107                                                                              3,366,569   3,513,093   3,649,659                                    3,216,936                                                                              3,367,943   3,533,945   3,658,836                                    3,254,025                                                                              3,373,111   3,539,633   3,697,574                                    3,256,185                                                                              3,403,102   3,573,010   3,702,757                                    3,278,550                                                                              3,442,808   3,579,450   3,703,536                                    3,280,234                                                                              3,455,831   3,591,598   3,704,308                                    3,281,428                                                                              3,455,832   3,600,372   3,708,522                                    ______________________________________                                    

(5) Interpolymers of oil-solubilizing monomers such as decylmethacrylate, vinyl decyl ether and high molecular weight olefins withmonomers containing polar substituents, e.g., aminoalkyl acrylates oracrylamides and poly-(oxyethylene)-substituted acrylates. These may becharacterized as "polymeric dispersants" and examples thereof aredisclosed in the following U.S. patents:

    ______________________________________                                        3,329,658        3,666,730                                                    3,449,250        3,687,849                                                    3,519,565        3,702,300                                                    ______________________________________                                    

The above-noted patents are incorporated by reference herein for theirdisclosures of ashless dispersants.

Extreme pressure agents and corrosion- and oxidation-inhibiting agentsare exemplified by chlorinated aliphatic hydrocarbons such aschlorinated wax; organic sulfides and polysulfides such as benzyldisulfide, bis(chlorobenzyl)disulfide, dibutyl tetrasulfide, sulfurizedmethyl ester of oleic acid, sulfurized alkylphenol, sulfurizeddipentene, and sulfurized terpene; phosphosulfurized hydrocarbons suchas the reaction product of a phosphorus sulfide with turpentine ormethyl oleate; phosphorus esters including principally dihydrocarbon andtrihydrocarbon phosphites such as dibutyl phosphite, diheptyl phosphite,dicyclohexyl phosphite, pentylphenyl phosphite, diphentylphenylphosphite, tridecyl phosphite, distearyl phosphite, dimethyl naphthylphosphite, oleyl 4-pentylphenyl phosphite, polypropylene (molecularweight 500)-substituted phenyl phosphite, diisobutyl-substituted phenylphosphite; metal thiocarbamates, such as zinc dioctyldithiocarbamate,and barium heptylphenyl dithiocarbamate; Group II metalphosphorodithioates such as zinc dicyclohexylphosphorodithioate, zincdioctylphosphorodithioate, barium di(heptylphenyl)phosphorodithioate,cadmium dinonylphosphorodithioate, and the zinc salt of aphosphorodithioic acid produced by the reaction of phosphoruspentasulfide with an equimolar mixture of isopropyl alcohol and n-hexylalcohol.

Other additives useful in fuels include deposit preventers or modifierssuch as triaryl phosphates, dyes, cetane improvers, antioxidants such as2,6-di-tertiary-butyl-4-methylphenol, rust inhibitors such as alkylatedsuccinic acids and anhydrides, bacteriostatic agents, gum inhibitors,metal deactivators, demulsifiers and the like.

The magnesium complexes of this invention can be added directly to thelubricant or fuel. Preferably, however, they are diluted with asubstantially inert, normally liquid organic diluent such as thosementioned hereinabove, particularly mineral oil, naphtha, benzene,toluene or xylene, to form an additive concentrate. These concentratesgenerally contain about 20-90% by weight of the magnesium complex andmay contain in addition, one or more of the other additives describedhereinabove.

CORROSION-RESISTANT COATINGS AND OTHER USES

The thixotropic magnesium complexes of this invention, especially thosethat are viscous or solid at ambient temperatures, are useful ascorrosion-resistant coatings for metal (e.g., ferrous metal, galvanized,aluminum or magnesium) surfaces, especially in the nature of undercoatsfor automotive bodies, coatings for structural members such asautomotive frames, and the like. They may be employed as such alone orin combination with various adjuvants known to be useful in suchcoatings, such as other basic metal sulfonates (of the type disclosed inU.S. Pat. No. 3,453,124, which is incorporated by reference herein forsuch disclosure), acidic phosphate esters, and waxes and resins asdisclosed hereinabove with reference to component D.

For coating automotive frames and the like, a solid "hot melt"composition is suitable. Frequently, a dye or pigment is added to the"hot melt" composition.

For corrosion-inhibiting purposes, the viscous or solid composition ofthis invention may be applied to the metal surface by any ordinarymethod such as brushing, spraying, dip-coating, flow-coating,roller-coating and the like, with heating if necessary (as to liquefy asolid composition). The viscosity may be adjusted for the particularmethod of application selected by adding, if necessary, a diluent whichmay be a substantially inert, normally liquid organic diluent, ananalogous solid, or a mixture of liquids and solids; suitable materialsas described hereinabove with reference to component D. The coated metalsurface may then be dried either by exposure to air or by baking,although drying frequently takes place without a separate drying step.If the coating composition is of a suitable viscosity to allow directapplication to the metal surface, no solvent is used and no dryingprocedure need be followed. A more viscous grease can be diluted toproduce a less viscous grease which is suitable for application aspreviously noted. The film thickness is not critical although a coatingof about 50-2000 mg. per square foot of surface in the case of anundercoat, and up to about 10,000 mg. per square foot in the case of acoating for frames or other structural members, is usually sufficient toprovide adequate protection. Heavier coatings can be used if desired,but they normally contribute little in the way of additional protection.

The magnesium complexes of this invention are also useful as lubricantgreases and as stabilizers for resinous compositions, typicallypolyvinyl chloride, to protect them against oxidative degradation.

What is claimed is:
 1. A method for preparing a thixotropicnoncarbonated magnesium-containing complex which comprises heating, at atemperature above about 30° C., a mixture comprising:(A) at least one ofmagnesium hydroxide, magnesium oxide, hydrated magnesium oxide, and amagnesium alkoxide; (B) At least one oleophilic organic reagentcomprising a carboxylic acid, a mixture of a major amount thereof with aminor amount of a sulfonic acid or pentavalent phosphorus acid, or anester or alkali metal or alkaline earth metal salt of either of these;(C) Water, if necessary to convert a substantial proportion of componentA to magnesium hydroxide or hydrated magnesium oxide; and (D) At leastone organic solubilizing agent for component B; the ratio of equivalentsof magnesium to the acid portion of component B being at least about5:1, and the amount of water present, if any, being from 0.7 to 3.0moles per gram-atom of magnesium in component A.
 2. A method accordingto claim 1 wherein component D is at least one substantially inert,normally liquid organic diluent.
 3. A method according to claim 2wherein component B is a mixture of at least one alkylbenzenesulfonicacid and at least one carboxylic acid containing from about 8 to about30 carbon atoms.
 4. A method according to claim 1 wherein component D isat least one substantially inert organic material which is solid atambient temperature.
 5. A method according to claim 4 wherein componentB is a mixture of at least one alkylbenzenesulfonic acid and at leastone caboxylic acid containing from about 8 to about 30 carbon atoms. 6.A method according to claim 1 wherein component D is a mixture of atleast one substantially inert organic material which is solid at ambienttemperature with at least one substantially inert, normally liquidorganic diluent.
 7. A method according to claim 6 wherein component B isa mixture of at least one alkylbenzenesulfonic acid and at least onecarboxylic acid containing from about 8 to about 30 carbon atoms.
 8. Athixotropic complex prepared by the method of claim 2 or
 3. 9. Anadditive concentrate comprising a substantially inert, normally liquidorganic diluent and a complex according to claim
 8. 10. A compositioncomprising a major amount of a lubricating oil and a minor amount of acomplex according to claim
 8. 11. A composition comprising a majoramount of a normally liquid fuel and a minor amount of a complexaccording to claim
 8. 12. A thixotropic complex prepared by the methodof any one of claims 4-7.
 13. A complex according to claim 12 which issolid at ambient temperature.
 14. A composition comprising a complexaccording to claim 12 to which a portion of component D has been addedafter preparation thereof.
 15. A composition comprising a complexaccording to claim 13 to which a portion of component D has been addedafter preparation thereof.
 16. A composition comprising a complexaccording to claim 12 and a minor effective amount of an oxidationinhibitor.
 17. A composition comprising a complex according to claim 13and a minor effective amount of an oxidation inhibitor.
 18. Acomposition comprising a complex according to claim 14 and a minoreffective amount of an oxidation inhibitor.
 19. A composition comprisinga complex according to claim 15 and a minor effective amount of anoxidation inhibitor.